docs: Clean redundant relative links.

We previously had a convention of redundantly including the directory
in relative links to reduce mistakes when moving content from one file
to another.  However, these days we have a broken link checker in
test-documentation, and after #21237, MyST-Parser will check relative
links (including fragments) when you run build-docs.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

docs/development/authentication.md

@@ -138,9 +138,9 @@ details worth understanding:
 Some OAuth providers (such as Facebook) require HTTPS on the callback
 URL they post back to, which isn't supported directly by the Zulip
 development environment. If you run a
-[remote Zulip development server](../development/remote.md), we have
+[remote Zulip development server](remote.md), we have
 instructions for
-[an nginx reverse proxy with SSL](../development/remote.html#using-an-nginx-reverse-proxy)
+[an nginx reverse proxy with SSL](remote.html#using-an-nginx-reverse-proxy)
 that you can use for your development efforts.
 
 ## Testing LDAP in development

docs/development/overview.md

@@ -76,12 +76,12 @@ machine, take a look at our tips for
 [developing remotely][dev-remote].
 
 [dev-remote]: remote.md
-[install-direct]: ../development/setup-advanced.html#installing-directly-on-ubuntu-debian-centos-or-fedora
-[install-vagrant]: ../development/setup-vagrant.md
+[install-direct]: setup-advanced.html#installing-directly-on-ubuntu-debian-centos-or-fedora
+[install-vagrant]: setup-vagrant.md
 [self-install-remote]: #installing-remotely
 [self-slow-internet]: #slow-internet-connections
-[configure-proxy]: ../development/setup-vagrant.html#specifying-a-proxy
+[configure-proxy]: setup-vagrant.html#specifying-a-proxy
 [using-dev-env]: using.md
 [testing]: ../testing/testing.md
 [ci]: ../git/cloning.html#step-3-configure-continuous-integration-for-your-fork
-[install-via-wsl]: ../development/setup-advanced.html#installing-directly-on-windows-10-with-wsl-2
+[install-via-wsl]: setup-advanced.html#installing-directly-on-windows-10-with-wsl-2

docs/development/remote.md

@@ -270,8 +270,8 @@ Next, read the following to learn more about developing for Zulip:
 - [Using the development environment][rtd-using-dev-env]
 - [Testing][rtd-testing]
 
-[install-direct]: ../development/setup-advanced.html#installing-directly-on-ubuntu-debian-centos-or-fedora
-[install-vagrant]: ../development/setup-vagrant.md
+[install-direct]: setup-advanced.html#installing-directly-on-ubuntu-debian-centos-or-fedora
+[install-vagrant]: setup-vagrant.md
 [rtd-git-guide]: ../git/index.md
 [rtd-using-dev-env]: using.md
 [rtd-testing]: ../testing/testing.md

docs/development/request-remote.md

@@ -70,13 +70,13 @@ Once your remote dev instance is ready:
 
 Once you've confirmed you can connect to your remote server, take a look at:
 
-- [developing remotely](../development/remote.md) for tips on using the remote dev
+- [developing remotely](remote.md) for tips on using the remote dev
   instance, and
 - our [Git & GitHub guide](../git/index.md) to learn how to use Git with Zulip.
 
 Next, read the following to learn more about developing for Zulip:
 
-- [Using the development environment](../development/using.md)
+- [Using the development environment](using.md)
 - [Testing](../testing/testing.md)
 
 [github-join]: https://github.com/join

docs/development/setup-advanced.md

@@ -21,9 +21,9 @@ that's running one of:
 You can just run the Zulip provision script on your machine.
 
 **Note**: You should not use the `root` user to run the installation.
-If you are using a [remote server](../development/remote.md), see
+If you are using a [remote server](remote.md), see
 the
-[section on creating appropriate user accounts](../development/remote.html#setting-up-user-accounts).
+[section on creating appropriate user accounts](remote.html#setting-up-user-accounts).
 
 :::{warning}
 There is no supported uninstallation process with this
@@ -50,7 +50,7 @@ source /srv/zulip-py3-venv/bin/activate
 
 Once you've done the above setup, you can pick up the [documentation
 on using the Zulip development
-environment](../development/setup-vagrant.html#step-4-developing),
+environment](setup-vagrant.html#step-4-developing),
 ignoring the parts about `vagrant` (since you're not using it).
 
 ## Installing directly on Windows 10 with WSL 2
@@ -151,7 +151,7 @@ installation method described here.
    to open VSCode connected to your WSL environment.
 
 1. You're done! You can pick up the [documentation on using the
-   Zulip development environment](../development/setup-vagrant.html#step-4-developing),
+   Zulip development environment](setup-vagrant.html#step-4-developing),
    ignoring the parts about `vagrant` (since you're not using it).
 
 WSL 2 can be uninstalled by following [Microsoft's documentation][uninstall-wsl]

docs/development/setup-vagrant.md

@@ -151,7 +151,7 @@ Debian](https://docs.docker.com/install/linux/docker-ce/debian/).
 #### Windows 10
 
 :::{note}
-We recommend using [WSL 2 for Windows development](../development/setup-advanced.html#installing-directly-on-windows-10-with-wsl-2).
+We recommend using [WSL 2 for Windows development](setup-advanced.html#installing-directly-on-windows-10-with-wsl-2).
 :::
 
 1. Install [Git for Windows][git-bash], which installs _Git BASH_.
@@ -1041,7 +1041,7 @@ remove the `GUEST_CPUS` and `GUEST_MEMORY_MB` lines from
 [cygwin-dl]: https://cygwin.com/
 [vagrant-dl]: https://www.vagrantup.com/downloads.html
 [vbox-dl]: https://www.virtualbox.org/wiki/Downloads
-[install-advanced]: ../development/setup-advanced.md
+[install-advanced]: setup-advanced.md
 [rtd-git-guide]: ../git/index.md
 [rtd-testing]: ../testing/testing.md
 [rtd-using-dev-env]: using.md

docs/development/using.md

@@ -93,7 +93,7 @@ See the mobile project's documentation on [using a development server
 for mobile development][mobile-dev-server].
 
 [rest-api]: https://zulip.com/api/rest
-[authentication-dev-server]: ./authentication.md
+[authentication-dev-server]: authentication.md
 [django-runserver]: https://docs.djangoproject.com/en/3.2/ref/django-admin/#runserver
 [new-feature-tutorial]: ../tutorials/new-feature-tutorial.md
 [testing-docs]: ../testing/testing.md